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Database of Antiretroviral Drug Interactions

Interactions between Antipsychotics and Antiretrovirals

Interactions with Clozapine
Antiretroviral (ARV)Dose of ARVDose of ClozapineEffect on ARV LevelsEffect on Clozapine LevelsPotential Clinical EffectsMechanism of InteractionManagement
Amprenavir60
(APV)(Agenerase)
- - - Not studied; may increase clozapine levelsIncreased clozapine effects-

Monitor and adjust clozapine as needed

"-" indicates that there are no data available
Interactions with Olanzapine
Antiretroviral (ARV)Dose of ARVDose of OlanzapineEffect on ARV LevelsEffect on Olanzapine LevelsPotential Clinical EffectsMechanism of InteractionManagement
Ritonavir175
(RTV)(Norvir)
500 mg BID10 mg QDNot studiedOlanzapine AUC: decreased 53%; half-life: decreased 50%; clearance: increased 115%; Cmax: decreased 40%Decreased olanzapine effectsInduction of CYP450 1A2 by ritonavir

Monitor and adjust olanzapine as indicated

"-" indicates that there are no data available
Interactions with Pimozide
Antiretroviral (ARV)Dose of ARVDose of PimozideEffect on ARV LevelsEffect on Pimozide LevelsPotential Clinical EffectsMechanism of InteractionManagement
Amprenavir60
(APV)(Agenerase)
- - - Not studied; may increase pimozide levelsIncreased pimozide effects (eg, hypotension, cardiac arrhythmias)Inhibition of CYP450 3A4 by amprenavir

Do not coadminister

Atazanavir
(ATV)(Reyataz)
---Not studied; may increase pimozide levelsIncreased pimozide effects (eg, hypotension, cardiac arrhythmias)Inhibition of CYP450 3A4 by atazanavir

Do not coadminister

Darunavir161
(DRV)(Prezista)
---Not studied; may increase pimozide levelsIncreased pimozide effects (eg, hypotension, cardiac arrhythmias)Inhibition of CYP450 3A4 by darunavir/ritonavir

Do not coadminister

Elvitegravir/cobicistat623
(Genvoya, Stribild)
----Potentially increased pimozide effects (e.g. cardiac arrhythmias)-

Do not coadminster

Indinavir177
(IDV)(Crixivan)
---May increase pimozide levelsIncreased pimozide effects (eg, hypotension, cardiac arrhythmias)Inhibition of CYP450 3A4 by indinavir

Do not coadminister

Antiretroviral (ARV)Dose of ARVDose of PimozideEffect on ARV LevelsEffect on Pimozide LevelsPotential Clinical EffectsMechanism of InteractionManagement
Lopinavir/ritonavir78
(LPV/r)(Kaletra)
---Not studied; may increase pimozide levelsIncreased pimozide effects (eg, hypotension, cardiac arrhythmias)Inhibition of CYP450 3A4 by lopinavir/ritonavir

Do not coadminister

Nelfinavir177
(NFV)(Viracept)
---Not studied; may increase pimozide levelsIncreased pimozide effects (eg, hypotension, cardiac arrhythmias)Inhibition of CYP450 3A4 by nelfinavir

Do not coadminister

Ritonavir178
(RTV)(Norvir)
---Not studied; may increase pimozide levelsIncreased pimozide effects (eg, hypotension, cardiac arrhythmias)Inhibition of CYP450 3A4 by ritonavir

Do not coadminister

Saquinavir44, 176
(SQV)(Fortovase, Invirase)
---Not studied; may increase pimozide levelsIncreased pimozide effects (eg, hypotension, cardiac arrhythmias)Inhibition of CYP450 3A4 by saquinavir

Do not coadminister

Tipranavir154
(TPV)(Aptivus)
---Not studied; may increase pimozide levelsIncreased pimozide effects (eg, hypotension, cardiac arrhythmias)Inhibition of CYP450 3A4 by tipranavir/ritonavir

Do not coadminister

"-" indicates that there are no data available
Interactions with Quetiapine
Antiretroviral (ARV)Dose of ARVDose of QuetiapineEffect on ARV LevelsEffect on Quetiapine LevelsPotential Clinical EffectsMechanism of InteractionManagement
Elvitegravir/cobicistat699
(Genvoya, Stribild)
---Not studied; potential increased quetiapine AUCPossible increased risk of quetiapine adverse effects-

For patients currently on elvitegravir/cobicistat: initiate quetiapine at lowest possible dose. Titrate accordingly and monitor for adverse effects. If patient already on quetiapine and requiring new elvitegravir/cobicistat: reduce queitapine to 1/6 of original dose. Titrate and monitor efficacy and adverse effects

Elvitegravir/ritonavir-boosted protease inhibitor
--- Not studied; potential increased quetiapine AUCPossible increased risk of quetiapine adverse effects-

For patients currently on elvitegravir/cobicistat: initiate quetiapine at lowest possible dose. Titrate accordingly and monitor for adverse effects. If patient already on quetiapine and requiring new elvitegravir/cobicistat: reduce queitapine to 1/6 of original dose. Titrate and monitor efficacy and adverse effects

"-" indicates that there are no data available
 44:Fortovase [package insert]. Basel, Switzerland: F. Hoffman-La Roche Ltd.;2003.
 60:Agenerase [package insert]. Research Triangle Park, NC: Glaxo Wellcome Inc; 2004.
 78:Kaletra [package insert]. North Chicago, IL: Abbott Laboratories; Oct 2005.
 154:Aptivus [package insert]. Ridgefield, CT: Boehringer Ingelheim Pharmaceuticals, Inc.; Nov 2005.
 161:Prezista [package insert]. Raritan, NJ: Tibotec Therapeutics Inc.; April 2010.
 175:Penzak SR, Lawhorn WD, Hon YY, et al. Influence of ritonavir and CYP1A2 genotype on olanzapine disposition in healthy subjects [abstract #A-493]. 41st Interscience Conference on Antimicrobial Agents and Chemotherapy; 2001 December 16-19; Chicago, Illinois.
 176:Invirase [package insert]. Roche Laboratories Inc, Nutley, NJ; Sept 2005.
 177:Orap [package insert]. Sellersville, PA: Teva Pharmaceuticals; 1999.
 178:Dresser GK, Spence JD, Bailey DG. Pharmacokinetic-pharmacodynamic consequences and clinical relevance of cytochrome P450 3A4 inhibition. Clin Pharmacokinet 2000;38:41-57.
 623:Stribild [package insert]. Foster City, CA: Gilead Sciences, Inc.; August 2012.
 699:Panel on Antiretroviral Guidelines for Adults and Adolescents. Guidelines for the use of antiretroviral agents in HIV-1-infected adults and adolescents. Department of Health and Human Services. Available at http://aidsinfo.nih.gov/contentfiles/lvguidelines/AdultandAdolescentGL.pdf.